If i reinstall the OS on my macbook pro will it wipe my hard drive clean? Do I have an option?

Side note:

The reason is because I am having some Photoshop CS4 issues with the license being expired and I have researched and executed every plausable option to fix this, and I'm afraid the only option I have left is to move my stuff onto an external and wipe it clean and reinstall.

1) Do a clean install by booting into Mac OS X 'live disk' making sure that install disc is in the machine before hand. Then go to disk utilities and format disc and call it whatever you want. Then simply run the installer and follow instructions. Start over again with all files.

2) Same as one, except you will have previously used Time Machine to back everything up. And through installation it will allow the option to use a Time Machine backup.

MacRumors attracts a broad audience
of both consumers and professionals interested in
the latest technologies and products. We also boast an active community focused on
purchasing decisions and technical aspects of the iPhone, iPod, iPad, and Mac platforms.